8-haloxanthine salts of cyclic-aminoalkyl benzohydryl ethers and the production thereof



Patented Dec 19, 1950 UNITED PATENT *O-F'Fl C E 48 HAQLUXANTHI NE 'TSALTYS QGF CECLIC-AMI- 'NOALKYL BENZOHYDRYL {ETHERS AND THE PRODUCTION THEREOF John W. ('Jusic, Skokie, Ill., -assignor to D. -Searle & (30., Chicago, 111., a corporation of *Illinois 'No Dr awing Application .lfanuary 21, 1950, Serial "N0. 139,970

12 Claims. '1

This "invention relates to halox'a'nthine compounds of *diarylalky-l ethers of aminoalkanols and to the productionthereof. More particularly this invention relates to 8-halo'xan'thi-ne salt's'o'f organic bases having the following general structural formula Ar n c oflnk e wherein .Ar and Ar are'aryl radicals, Ri's a lower alkyl'radical or a hydrogen atom, All; ls'a lower alkylene radical, and B is an aliphatic-type organic amino radical.

This application is a continuation-"impart of my copending application Serial No. s2,'2's4,-fi1ed March 18, 1949, now U. S. Patent No. .2,'499;058, granted February 28, I950.

In the foregoing structural formula Ar and A1" represent lower ar-yl radicals which may be the same or different. Among 'such radicals are phenyl, tolyl, chlorophenyl, bromophenyl, iodophenyl, methox-ypheny-l, ethoXyph e-nyl, xy'lyl, and similar aryl radicals of the benzene series. B represents hydrogen or a lower alkyl radical-such as meth ylor ethyl. Alk represents loweralkylene radicals suc'h-"as ethylene, propylene, or the biitylene "radicals, and 'polymethy'lene r adi'c'aIs such as trime'thylene and "tetrameth'ylene. The amino radical EB represents aliphatic-type amineradicals, such as monoand di(lower alkyl'laiiiino radicals, wherein the "lower 'alkyl radicals may be the same or difierent and the corresponding monoand di('hydroxya'lkyl) amino radicals containing one or two hydroxyl groups. As used herein, lower alkyl means a primary -or secondary alkyl radical containing 1 to 5 carbon atoms. B also may represent cyclic amino radicals and saturated heterocycli'c amino radicals which are aliphatic in character. It includes amino groups such as cycl'ohexylamino, cyc1o pentylamino, morpholino, piper idino, thiamorpholino, and. alkyl derivatives of such amino radicals. B therefore represents a non-aromatic amino radical derived from an organic amine having dissociation constant in the range of 1 10- to 1 10 It is widely recognized that diariylalkyl ethers of aminoalkanols elicit certain undesirable side reactions and toxic manifestations. The most common efiects are dizziness and sleepiness fol- .lowing the administration of the medication. In

certain cases there may be nausea and vomiting. Other effects which have been noticed include weakness, narcolepsy, indigestion, coldness of the the individual coizi iponent's alone.

extremities, eizhaus'tio irritability, blurred vision, confusion, and in rare instances collapse. The symptoms produced by dianylalkyl ethers :of aininoailka'nols are often severe enough :to warrant reduced dosage or discontinuance of the medication.

it is the object of this invention to produce therapeutic compositions of matter which are relatively free from untoward reactions. A further object is to produce compositions of diarylalkyl e'thers of -arhi'nbalkanol's and haloxanthines of reduced toxicity. Another object :is to produce compositions having enhanced therapeutic (if my invention are SO tree f-foinflndesi i'abl sid'e effects that they may actually be used in sup pressing those undesirable symptoms commonly elicited by the usual antih iSta'm-in'ic drug's. Ear instance, my compounds can be used to vprevent or alleviate nausea, motion sickness,*diziiness and other distressing reactions.

7 Among the halogenated Xanthines to which this invention pertains are "the 'chloro, 'bromo, "and iiodo "derivatives of the'ophylline and related Ranthines which have a hydrogen atom in position "7.

In particular this invention is concerned with acidic 'xantlii'nes such as S chlor'otheophylline 8-bromotheop'hylline 8-chloroxanthine 3-methyle8 chlorckanthine 8-bromoxanthine 3-methy1-8'-bromoxanthine 1.,3-diethyl-8-bromoxanthine 1,3-diethyl-S-chlorGXanthine '8-io'dotheop'hylline 8-"iodo- 1,3 metnymantmne Gempo'si-tions of organic bases and na1exanthines are "readily prepared by dissolving the'ba's'e in a Suitable Solvent and treating the resulting solution with a solution of a halogenated xanthine. Solvents which are satisfactory for this reaction include the lower alcohols and ketones and their mixtures with water, ethers and hydrocarbons. Generally small excesses of the organic bases are desirable in these synthetic procedures. The desired salt generally crystallizes out of the solution on chilling or standing, or may be precipitated by addition of a solvent such as ether or benzene. A simple and efficient alternative method is that of heating together at 50-100 C. equivalent amounts of the liquid organic base and of the haloxanthine, with good mixing with a small amount of water or alcohol. As the materials react the mixture generally forms a thick paste or granular solid. On chilling the product becomes hard and solid and may be broken up, ground to a powder and dried. The compounds of this invention can also be produced by refluxing a solution of an ammonium salt of a haloxanthine in a lower alcohol or ketone with an equivalent of the organic base. During the heating, ammonia is evolved and the haloxanthine salt of the organic base is formed. On chilling this salt precipitates.

The following examples illustrate in more detail my invention, but in no way are to be construed as limiting it in spirit or in scope.

Ercample 1 A mixture of 30 g. of ,B-morpholinoethyl benzohydryl ether and 21.5 g. of S-chlorotheophylline is agitated with 100 cc. of boiling methyl ethyl ketone containing cc. of water. The resulting hot solution is treated with activated charcoal, filtered hot and evaporated to approximately one half its volume. The solution is then chilled and diluted with ether. The precipitate of the 8-chlorotheophylline salt of p-morpholinoethyl benzohydryl ether is removed and dried. A sample on analysis showed 6.59% chlorine. The calculated value is 6.73%.

Example 2 29.5 g. of p-morpholinoethyl benzohydryl ether and 26 g. of 8-bromotheophylline are dissolved in a boiling mixture of 100 cc. of methyl ethyl ketone and cc. of water. The boiling solution is filtered and evaporated under vacuum on the steam bath. The residue of the 8-bromotheophylline salt of ji-morpholinoethyl benzohydryl ether is triturated with ether, removed and dried.

A sample on analysis showed 14.19% bromine. The theoretical value is 14.41%.

Example 3 A solution of 98.6 g. of B-chloroethyl benzohydryl ether and 99 g. of cyclohexylamine in 200 cc. of butanone containing 5 g. of potassium iodide is refluxed for 3-4 days. The mixture is added to about 500 cc. of water, and the resulting mixture is made alkaline and extracted with ether. The ether extract is dried and evaporated.

The residue of B-cyclohexylaminoethyl benzohydryl ether distills at 170-175" C. at 1.5 mm. pressure.

6 g. of the foregoing ether and 4 g. of 8-chlorotheophylline are dissolved in the minimum amount of hot butanone (100 cc. of butanone diluted with 4 cc. of water). The hot solution is filtered and allowed to cool slowly. There are deposited crystals of the 8-chlorotheophylline salt of p-cyclohexylaminoethyl benzohydryl ether. These are removed, washed with cold butanone and dried. A sample on analysis showed 6.41% chlorine. The calculated value is 6.58%.

Example 5 21 g. of benzohydryl p-(N-p-hydroxyethylmethylamino ethyl ether and 20 g. of 8-chlorotheophylline are dissolved in the minimum amount of warm aqueous methyl ethyl ketone and filtered. The filtrate is chilled and crystals of the 8-chlorotheophylline salt of benzohydryl ,8- (N 3-hydroxyethyl-methylamino) ethyl ether separate. These are removed and dried, and melt at 225-230 C.

Example 6 A hot solution of 23.2 g. of ammonium 8- chorotheophyllinate and 25.5 g. of ,B-dimethylaminoethyl benzohydryl ether in cc. of isopropanol and 10 cc. of water is refluxed for 4 hours. On chilling the salt precipitates. This is removed by filtration, washed with ether and dried. The 8-chlorotheophylline salt of fl-dimethylaminoethyl benzohydryl ether so prepared melts at 102404 C. After recrystallization from ethyl acetate it melts at 104-105" C.

I claim: 1. A salt of a basic ether of the formula Ce a CH-OAlk-B with an 8-haloxanthine containin a hydrogen atom in the 7-position, wherein Alk is a lower alkylene radical and B is an amino radical selected from the class consisting of morpholino, piperidino, cyclopentylamino, and cyclohexylamino radicals and lower alkyl derivatives thereof.

2. A salt of a morpholinoethyl benzohydryl ether with an 8-haloxanthine having a hydrogen atom in position '7.

3. A salt of B-morpholinoethyl benzohydryl ether with an 8halotheophylline.

4. The 8-chlorotheophylline salt of fi-morpholinoethyl benzohydryl ether.

5. The 8-bromotheophylline salt of B-morpholinoethyl benzohydryl ether.

6. The process of claim 7 wherein the solvent is methyl ethyl ketone.

'7. The process of producing a salt of a basic ether and an S-haloxanthine containing a hydrogen atom in the 7-position, said basic ether having the formula Co s wherein Alk is a lower alkylene radical and B is an amino radical selected from the class consisting of morpholino, piperidino, cyclopentylamino, and cyclohexylamine radicals and lower alkyl derivatives thereof, which comprises mixing a member of the group consisting of an 8-haloxanthine which contains a hydrogen atom in the 7-position and the ammonium salt thereof, with 10. The 8-chlorotheophylline salt of fl-piperidinoethyl benzohydryl ether.

11. A salt of p-cyclohexylaminoethyl benzohydryl ether with an B-haloxanthine having a hydrogen atom in position 7.

12. The 8-chlorotheophyl1ine salt of fi-cyclohexylaminoethyl benzohydryl ether.

JOHN W. CUSIC.

No references cited. 

1. A SALT OF A BASIC EITHER OF THE FORMULA
 7. THE PROCESS OF PRODUCING A SALT OF A BASIC ETHER AND AN 8-HALOXANTHINE CONTAINING A HYDROGEN ATOM IN THE 7-POSITION, SAID BASIC ETHER HAVIN THE FORMULA. 